Reckless Driving: Gene drives and the end of nature - Seed Freedom
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Reckless Driving:
Gene drives and the end of nature
Imagine that by releasing a single fly into the wild Given the current feeble restraints on existing genetic
you could genetically alter all the flies on the engineering technologies, how would anyone be able to
planet—causing them all to turn yellow, carry a assess the risks of gene drives? Would the public be
toxin, or go extinct. This is the terrifyingly informed and have a say in how they would
powerful premise behind gene drives: a be used? And if an accident were to occur,
The ethical,
new and controversial genetic cultural and societal given that the damage would be
engineering technology that can implications of Gene drives massive and irreversible, who would
permanently alter an entire species are as enormous as the be held accountable?
by releasing one bioengineered ecological consequences. Civil The ethical, cultural and societal
individual. society groups are alarmed by implications of gene drives are as
Gene drives can entirely re-engineer this newfound ability to enormous as the ecological
ecosystems, create fast spreading reshape the natural consequences. Civil society groups (and
extinctions, and intervene in living world. even some gene drive researchers) are
systems at a scale far beyond anything ever alarmed by this newfound ability to reshape
imagined. When gene drives are engineered into a fast- the natural world. However, such an omnipotent power
reproducing species they could alter their populations to control nature is immensely tempting to those who
within short timeframes, from months to a few years, may not be constrained by either common decency or
and rapidly cause extinction. This radical new common sense. Gene drive technology is commanding
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technology, also called a “mutagenic chain reaction,” is the attention of the world’s most powerful military,
unlike anything seen before. It combines the extreme agribusiness, and social change organizations. Gene
genetic engineering of synthetic biology and new gene drive technology also appears to be relatively simple and
editing techniques with the idea that humans can and cheap, so it could easily fall into the hands of those,
should use such powerful unlimited tools to control including governments, who might use it as a weapon.
nature. Gene drives will change the fundamental
relationship between humanity and the natural world
forever. How does a Gene drive work?
The implications for the environment, food security, A trait is a genetically determined characteristic of an
peace, and even social stability are significant. Dealing organism (e.g. eye color). In normal sexual
with this run-away technology is reproduction, a trait generally has only
already being compared to the This briefing was produced a 50% chance of being expressed. With
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challenge of governing nuclear power. by the Civil Society Working a gene drive, however, that trait is
Existing government regulations for the Group on Gene Drives which “driven” into the organism’s
includes Biofuelwatch, reproductive cycle so that every single
use of genetic engineering in agriculture
Econexus, ETC Group,
have allowed widespread genetic offspring always carries and expresses
Friends of the Earth US,
contamination of the food supply and Hawai’i SEED and Navdanya.
the specified trait.
the environment.Gene drives force an artificially engineered
trait to spread through the natural Fig 1a. Normal inheritance in 4 generations of flies:
population until it becomes ubiquitous or
crashes that population. Altered gene
The first working gene drives were does not spread
demonstrated at the end of 2014 using a
new gene-editing technique known as
CRISPR-CAS9. They work by setting up
a genetic enforcement mechanism which
copies itself from parent to child, cascading
from one generation to the next by sexual
reproduction. Gene drives only work in
sexually reproducing species. The natural
process of inheritance through sexual
reproduction is the cornerstone of
biological diversity within a species. But
Fig 1b. Gene drive inheritance in 4 generations of flies:
gene drives force a species towards
uniformity or extinction—a perfectly anti-
ecological outcome and a violation of the
Altered gene
fundamentals of evolution. always spreads
For example, when a gene drive
commands an organism to glow green, the
“mutagenic chain reaction” that follows
ensures that all future progeny of that
organism, and all its descendants, also glow
green. This violates the normal rules of
species evolution, which usually limits the
passing on of a new trait to only some
offspring and limits its survival to those
that have a selective advantage.
The implications for natural populations are striking. If someone wanted to ‘crash’ a species and cause its
Figure 1a. shows the normal pattern of inheritance extinction, they would simply engineer a gene drive that
across the generations. Following the established rules makes all the offspring into males, for instance. This
of genetics, we can expect roughly 50% of an organism’s approach is being taken with the so-called ‘daughterless'
offspring to carry a specific gene. Once that altered mouse gene drive. Any mouse that the daughterless
organism is introduced into a population, the number mouse mates with will only give birth to males. In turn,
of affected organisms can dilute through the all their progeny will only produce males and they will
generations. But with a gene drive (see figure 1b.) there spread the ‘daughterless’ trait until they overwhelm that
is 100% inheritance of the new trait enforced among all mouse species and crash the population. Theoretically,
descendants. Instead of being diluted, the new trait this “male-only” mechanism could be used with any
takes over. sexually reproducing organism.
2 Reckless Driving - Gene Drives and the end of natureExamples of various gene drives Split drive: a technique where half a gene drive is
engineered into an organism’s DNA, and half into a
piece of associated virus DNA, so that the organism
Global drives: a “standard” gene drive that continues won’t pass on the full instructions for a new gene
to spread, potentially until it takes over the entire drive.4 This is intended for lab safety but is
species (or causes the entire species to go extinct). impractical as a technology in the wild.
Reversal Drive: a speculative proposal to ‘undo’ the Daisy drive: a proposed gene drive that theoretically
effects of a gene drive by sending a second drive after stops working after a certain number of generations.
the first. A recent report from the US National This is supposed to create ‘local’ gene drives that
Academy of Sciences was skeptical that this idea won’t spread uncontrollably.5 The inventor, Kevin
would reliably work.3 Esvelt, acknowledges that a daisy drive could mutate
into a global drive accidentally.
How can gene drives be used?
1. Industrial Agriculture Releasing an engineered gene drive into agricultural
Gene drive developers acknowledge that agribusiness is fields could attack a country’s food production. And
interested in this technology for many uses. These gene drive mosquitoes and other insects could be
include eradicating weeds (a “sensitizing gene drive” engineered to spread lethal toxins in their bite.8
could be released into wild weed species to make it 3. Attacking Disease
more susceptible to a proprietary herbicide such as
Much of the hype around pesticides promised that they
roundup), or eliminating pests. For example, gene drive
would safely eradicate pests, but in fact they are, as
research on fruit flies—specifically on species like
Rachel Carson called them, “biocides” that kill
Drosophila Suzukii, which attack soft fruit harvests—is
indiscriminately. While the promised benefits of gene
intended to eradicate it globally and save on the costs of
drives are that they will target organisms that carry
both pesticides and lost crop damages.6 Other pests
disease, there is no firm scientific basis for the claim that
that might be driven to extinction to protect industrial
their impact will not spread beyond the intended target.
agriculture include mice, moths and locusts. Gene
The following are currently being developed as gene
drives may also be used to speed up the introduction of
drive organisms under the guise of eradicating disease:
a genetically modified trait into seed harvests.
Mosquitos: Several teams are working on gene drives
2. Military
that would eradicate mosquitos or re-engineer them so
Gene drives are a classic ‘dual use’ technology, meaning
they are unable to carry malaria. Theoretically the
that the technology for gene drives developed for one
mosquitos that carry Zika and Dengue could also be
use could also be used as a weapon or biological agent.
attacked with gene drive systems.
For example, work is already underway to equip
Parasitic worms: At least one team is working on gene
parasitic worms with gene drives in order to eradicate
drives to attack the worms that cause schistosomiasis
them7–the same technology could be used to make
and others propose gene drives for whipworm and
them spread disease or toxins. Gene-drive yeasts have
threadworm.9
been created in the lab and these could be engineered to
be harmful to humans.
Civil Society Working Group on Gene Drives www.synbiowatch.org 34. Artificially Enhancing Conservation They call this the GBIRd project (Genetic Biocontrol
of Invasive Rodents) and intend to release these gene
A small group of conservationists argue that tools that
drives by 2020.10 Additionally, there is a highly
cause deliberate extinction could be harnessed for good.
promoted proposal to develop gene drive mosquitoes
A consortium of 5 partners (including two government
for release in Hawaii where one species of mosquito
agencies) led by the conservation group Island
carries a form of avian malaria that affects native birds,11
Conservation is developing gene drive-equipped mice
despite the fact that at least one targeted bird species
that will be released on islands ostensibly to kill the
has developed a natural resistance to avian malaria and
mice that harm birds.
there are still disease free areas.12 This project is being
promoted by The Long Now Foundation’s Revive and
Restore project.13
What are the environmental dangers of gene drives?
Greater threat of unintended consequences Could gene drives jump species?
Gene drives carry the same biosafety risks that other Promoters of gene drives present them as precise
genetically engineered organisms carry and more. We mechanisms, just as GMO promoters did. But living
know the track record of genetically modified systems and sexual reproduction processes are messy
organisms (GMOs) acting in unexpected ways and and unpredictable. We now know there is occasional
causing a variety of environmental harms, while not horizontal gene transfer (movement of genes between
delivering on their promised benefits. Gene drives are different species) and that some genes do cross over into
designed not only to spread rapidly but also to do it related species.
with exponential efficiency. There is nothing in the Applying gene drives to agriculture will intensify
natural world to compare them to and that limits our existing concerns about the use of genetic engineering
capacity to predict their behavior. and monocultures in industrial agriculture. Gene drive
Severing a strand in the ecological web strategies may strengthen the market monopoly of
Gene drives are designed to create large-scale changes in agribusiness giants such as Monsanto and Syngenta,
populations and intentionally impact entire ecosystems. especially if wild weed populations are altered to
We know so little about the web of life as it is, are we respond to their proprietary chemicals or wide patent
really ready to take such radical steps to alter the course claims are applied. The decision to eradicate wild weed
of evolution? It’s impossible to predict the ecological populations may also harm culturally significant crops
consequences of such a rapid, massive, unprecedented and indigenous species. For example, proposals to use
disruption. Removing a pest may seem attractive, but gene drives against pigweed in North America (Palmer
even pests have their place in the food chain. Amaranth) could also eradicate species of amaranth
Additionally, eradicating one species might used for food and cultural purposes in Central
unpredictably open up space for the expansion of America.14
another species which may carry diseases, affect
pollination or otherwise threaten biodiversity.
4 Reckless Driving - Gene Drives and the end of natureDangers to society The need to police gene drives as a
The ethical, cultural and societal “We are walking potential bioweapon may expand and
implications of gene drives are forwards blind. We are deepen military control and
especially complex and challenging. opening boxes without thinking collusion in biotechnology
Civil society groups, and even about consequences. We are going developments.
some gene drive researchers, are to fall off the tightrope and lose the Proposals to unleash gene drives
trust of public.”
raising the alarm about the power as a ‘silver bullet’ for health and
– Gene drive developer
of this technology. Such a powerful conservation challenges are highly
Kevin Esvelt, MIT, on the current
tool may be too tempting to risky and speculative. But these
rising interest in gene drive
military funding agencies and hi-tech applications..15 “technofixes” continue to be over-
agribusiness who see advantages to sold to the public through deceptive
exploring this Pandora’s box. This raises the media campaigns, corruption of regulatory
basic question: who will this technology benefit agencies, and by inflaming the public’s fears and
and who decides how it will be used? anxieties about disease, climate change, and species
The potential threat of weaponized gene drives can’t extinction. “Silver bullet” technologies distract from,
be overstated. While a harmful gene drive could rather than contribute to, the work that needs to be
theoretically be engineered into a fast-spreading parasite done to root out the systemic causes of these problems
to ‘wipe out’ a population or used to crash a food – such as providing sanitation, defending human rights,
harvest, the bigger threat may come from the changing addressing poverty and upholding community land
geopolitics and security requirements that the existence rights and stewardship over nature.
of gene drives may unleash.
What should be done? We recommend:
“The project of • An immediate and international
The Civil Society Working Group
deliberately exterminating halt to gene drive releases and
on Gene Drives prepared this
species is a crime against nature experimentation.
briefing.17 We believe that no
and humanity… Developing tools
case can be made for proceeding • All existing patents on this
of extermination in the garb of
with gene drive experiments or technology should be either
saving the world is a crime. A
developments at this time. crime that must not be allowed extinguished as against the
Moreover, in our view, recent to continue any further.” public interest or handed to an
proposals to move ahead with real – Dr. Vandana Shiva, international agency charged with
16
world gene drive trials (e.g. the GBIRd India preventing licensing or use of the
project led by Island Conservation and the technology.
gene drive mosquito in Hawaii) are reckless and • Scientists, ethicists, environmental groups, civil
irresponsible and do not reflect the essential values of society groups, lawyers and even artists and poets
the conservation movement. Such projects should not must speak out clearly against gene drives in a
be funded or promoted by non-profit groups or concerted and public way, calling for the
philanthropic organizations whose social contract and withdrawal of support for the funding and
tax-exempt status is founded on the principle that continued promotion of gene drive technology.
they are doing a public service.
Civil Society Working Group on Gene Drives www.synbiowatch.org 5Footnotes 1 Gantz VM, Bier E. The mutagenic chain reaction: a method for converting heterozygous to homozygous mutations. Science (New York, NY). 2015;348(6233):442-444. doi:10.1126/science.aaa5945. 2 Jim Thomas, “The National Academies’ Gene Drive study has ignored important and obvious issues” The Guardian 9th June 2016. https://www.theguardian.com/science/politicalscience/2016/jun/09/the-national-academies-gene-drive-study-has- ignored-important-and-obviousissues 3 National Academies of Sciences, E ngineering, and Medicine. Gene Drives on the Horizon: Advancing Science, Navigating Uncertainty, and Aligning Research with Public Values. Washington, DC: The National Academies Press, 2016. doi:10.17226/23405. 4 Safeguarding CRISPR-Cas9 Gene Drives in yeast. James E DiCarlo, Alejandro Chavez, Sven L Dietz, Kevin M Esvelt & George M Church Nature Biotechnology 33, 1250–1255 (2015) doi:10.1038/nbt.3412 5 Kevin Esvelt, “‘Daisy drives’ will let communities alter wild organisms in local ecosystems.” https://medium.com/mit-media- lab/daisy-drives-will-let-communities-alter-wild-organisms-inlocal-ecosystems-cb626c5a9f38#.91i6eyhc0 6 Li F. and Scott M. J. (2016). CRISPR/Cas9-mediated mutagenesis of the white and Sex lethal loci in the invasive pest, Drosophila suzukii. Biochem Biophys Res Commun. 469 (4): 911-916. doi: 10.1016/j.bbrc.2015.12.081. web 7 George Washington University News release” MaxMind gives $100,000 to GW to create Gene Drive to eliminate schistosomiasis” Feb 1st 2016- http://www.eurekalert.org/pub_releases/2016-02/gwu-mg020116.php 8 Science. 2014 Aug 29;345(6200):1010. doi: 10.1126/science.345.6200.1010-b. Gene Drives raise dual-use concerns. 9 George Washington University News release “MaxMind gives $100,000 to GW to create Gene Drive to eliminate schistosomiasis” Feb 1st 2016. http://www.eurekalert.org/pub_releases/2016-02/gwu-mg020116.php 10 GBIRd project (Genetic Biocontrol of Invasive Rodents) led by Island Conservation International - details at http://www.islandconservation.org/program-coordinator/. 11 Antonio Regalado, “The Plan to Rescue Hawaii's Birds with Genetic Engineering” Technology Review, May 11th 2016. https://www.technologyreview.com/s/601383/the-plan-to-rescue-hawaiisbirds-with-genetic-engineering/ 12 Samuel, M. D., B. L. Woodworth, C. T. Atkinson, P. J. Hart, and D. A. LaPointe. 2015. Avian malaria in Hawaiian forest birds: infection and population impacts across species and elevations. Ecosphere 6(6):104. http://dx.doi.org/10.1890/ES14- 00393.1 13 http://reviverestore.org/case-studies/ 14 Vandana Shiva, “Biodiversity, GMOs, Gene Drives and the Militarized Mind” Common Dreams. July 10th 2016. http://www.commondreams.org/views/2016/07/10/biodiversity-gmos-gene-drivesand-militarized-mind 15 Kristen v Brown, “This scientist is trying to stop a lab-created global disaster” Fusion.net 27th June 2016. http://fusion.net/story/317396/kevin-esvelt-gene-drive-responsive-science/ 16 Vandana Shiva, “Biodiversity, GMOs, Gene Drives and the Militarized Mind” Common Dreams. July 10th 2016. http://www.commondreams.org/views/2016/07/10/biodiversity-gmos-gene-drivesand-militarized-mind 17 The Civil Society Working Group on Gene Drives includes Biofuelwatch, Econexus, ETC Group, Friends of the Earth US, Hawai’i SEED, Navdanya and independent author and lawyer Claire Hope Cummings, M.A., J.D. 6 Reckless Driving - Gene Drives and the end of nature
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